This invention relates to a three-dimensional display apparatus used as an output apparatus of an image processing apparatus such as, e.g., a so-called CAD (Computer Aided Design) and a computer.
Holography has been known as a technology to display three-dimensional images.
The holography is a method to reproduce a three-dimensional image by recording on a prescribed medium the interference fringes formed by the interference of the reference beam, i.e., a light from a laser or the like, and the object beam, i.e., the light reflected by an object that another light from the laser or the like irradiates, and by regenerating the image of the object by causing the same light as the reference beam to irradiate the recorded interference fringes. However, the holography cannot reproduce an arbitrary three-dimensional image according to inputs, and thus, has not yet been practically applied to an output means of an information apparatus and the like.
As another three-dimensional display apparatus to which a technology other than the holography is applied, there exists a virtual reality apparatus, as described in Japanese Patent Application Publication 2001-175883. The virtual reality apparatus has two-dimensional displays made of liquid crystal and the like for each of the right and left eyes of a viewer and shows images on the displays upon correcting images for the right and left eyes respectively according to the position of the image in the three-dimensional space so as to enable the viewer to perceive a pseudo three-dimensional image. The virtual reality apparatus can display an arbitrary three-dimensional image according to inputs by changing a correction value for correcting images for the right and left eyes respectively.
However, such a conventional virtual reality apparatus including the virtual reality apparatus described in Japanese Patent Application Publication 2001-175883 has a problem that it is very difficult for the viewer to do other works while wearing the display apparatus since the display apparatus should be fixed to the face of the viewer, and thus, the display apparatus is not suitable for displaying information or instruction relating to the work that the viewer is doing.
This invention has been made to solve such problem, and aims to provide a three-dimensional display apparatus suitable for displaying information or instruction relating to the work that the viewer is doing.